This problem is associated with an option we have in the software called Address Quick Recall.
From our Help Menu...
The Address Quick Recall option tries to match your entry to what you've previously entered. The quick recall feature is designed to save time and reduce errors during data entry. As you type the first character into a field, the quick recall tries to match the new entry to existing ones for that field. You can continue entering characters until the correct entry appears, then press tab (or click in another field) to accept the entry and move to the next field. The quick recall feature is used for the city, state, zip code, country, and list by fields.

Now to fix this problem. Quick Recall is displaying the closest match to one of your addresses records, so you have the name spelled wrong on one or more of your addresses. Make note of the incorrect spelling, then use our find feature (Binoculars button in toolbar) to locate the incorrect spelling. On the find screen, clear the search fields then select the field you want to search in. Type in the incorrect spelling and click Find Now. The addresses will be listed that have the incorrect spelling. If more than one jot the names down and go into them to change the problem; if just one, highlight it and hit the Select button it will take you to that Address record. Change the spelling mistakes.

This will stop the incorrect recall from showing up.